Question: Simplify the following expression: $k = \dfrac{6ts}{10rs + 6s} - \dfrac{4s^2 - 10rs}{10rs + 6s}$ You can assume $r,s,t \neq 0$.
Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{6ts - (4s^2 - 10rs)}{10rs + 6s}$ $k = \dfrac{6ts - 4s^2 + 10rs}{10rs + 6s}$ The numerator and denominator have a common factor of $2s$, so we can simplify $k = \dfrac{3t - 2s + 5r}{5r + 3}$